The present invention relates generally to an improved method and/or process for preparing and handling formulations useful in metal treatment baths, and more particularly to a method for preparing and packaging formulations useful in the preparation and replenishing of aqueous-based baths for simultaneously removing soil, grease and oils from metallic surfaces, while at the same time protecting these surfaces against corrosion. The present invention finds particular application in connection with products requiring short and/or intermediate term protection of their metallic surfaces as they are either shipped, stored or otherwise handled while awaiting further operations. Of particular interest is the protection of metallic surfaces of objects such as components, subassemblies and/or weldments which are partially completed in one production operation, and which must await transfer, shipment, and/or other indeterminate storage pending completion of the next operation.
The present invention involves an improved method or process for preparing working solutions of surface treating compounds by pre-blending surface cleaner and corrosion inhibitor components and packaging the resulting blends in water soluble pouches or containers. The method involves packaging water soluble vapor phase corrosion inhibiting chemicals (VCI) in combination with surface cleaners and/or detergents in water soluble pouches or containers so as to permit the addition of these components to baths without the necessity of hand involvement at this step of the process. The water soluble pouches or containers are preferably prepared from polyvinylalcohol (PVA) films, with the highly effective blends of surface cleaner and corrosion inhibiting components being compatible with PVA films, thus providing a significant shelf life for the pouches containing the components to be used in the working solutions.
In manufacturing and/or product processing operations, it has become common practice to manufacture certain components at a first facility or at a first location within a given facility, with the partially completed components being stored and/or held until needed for use in subsequent operations. An example of such a procedure would include a first operation for preparing a formed or configured component, with the component being held in inventory until needed for use and/or treatment in a subsequent operation. The subsequent operation may, for example, be to combine the component with a second component and then undergo the application of a surface coating for the combination. Because of the tendency of certain metallic surfaces to oxidize and/or corrode in the atmosphere, the application of a corrosion inhibitor to the surface is frequently undertaken to retard and/or prevent the creation of oxide layers and/or rust. Thus, in accordance with the present invention, parts prepared at one point in time for use at a later point in time may be cleaned and protected from corrosion and/or rust by treatment in a bath containing a blend of surface cleaners and corrosion inhibitors, with the working solution for the bath being prepared and replenished by the addition of surface cleaners and corrosion inhibitors blended in predetermined proportions and packaged in known quantities in water soluble pouches or containers. The components comprising the working solution may be maintained at their required concentration levels within the bath on an expeditious, effective and safe condition with the water soluble containers that can be added directly to the working solutions.